Throttle command outuput based on elapsed time
Throttle command outuput based on elapsed time

Throttling is now done in terms of time elapsed since the last output,
instead of calls per second as previously done.

For now, looks like 250ms throttle works fine.

Ref #92

jbrodriguez/unbalance,jbrodriguez/unbalance,jbrodriguez/unbalance,jbrodriguez/unbalance